Circuit breaker mechanism having auxiliary features mounted within an electrically isolated housing compartment



March 29, 1966 c. E. GRYCTKO 3,243,563

CIRCUIT BREAKER MECHANISM HAVING AUXILIARY FEATURES MOUNTED WITHIN AN ELECTRICALLY ISOLATED HOUSING CQMPARTMENT 4 Sheets-Sheet 1 Filed Oct. 10, 1963 N H N INVENTOR. 012.4 5 @eycmm flsrzaza/v/g 4 542; {L za/fawn,

March 29, 1966 c GRYCTKQ 3,243,563

CIRCUIT BREAKER MECHANISM HAVING AUXILIARY FEATURES MOUNTED WITHIN AN ELECTRICALLY ISOLATED HOUSING COMPARTMENT Filed Oct. 10, 1963 4 Sheets-Sheet 2 INVENTOR. (142! ii fYd/KO March 29, 1966 c. E. GRYCTKO 3,243,563

CIRCUIT BREAKER MECHANISM HAVING AUXILIARY FEATURES MOUNTED WITHIN AN ELECTRICAL-LY ISOLATED HOUSING COMPARTMENT United States Patent 3,243,563 CIRCUIT BREAKER MECHANISM HAVING AUXILIARY FEATURES MOUNTED WITHHN AN ELECTRICALLY ISOLATED HDUSING COMPARTMENT Carl E. Gryctko, Haddon Heights, N..I., assignor to I-T-E Circuit Breaker Company, Philadelphia, Pa., a corporation of Pennsylvania Filed Oct. 10, 1963, Ser. No. 315,312 8 Claims. (Cl. 200-168) This invention relates to molded case circuit breakers and more particularly to a multiphase circuit breaker of this type in which the auxiliary components are isolated from the current carrying elements of the circuit breaker phases.

In multiphase molded case circuit breakers of the prior art auxiliary components such as shunt trip devices, under voltage devices, and auxiliary switches are mounted in the very same compartments with the main current carrying elements of the circuit breaker. Because of this, isolating the auxiliary devices from the current carrying elements of the circuit breaker is a major problem.

In the instant invention this problem is solved in a novel manner by providing a three phase unit with a molded housing having five parallel compartments with the outer compartments and the central compartment each housing the current carrying elements for a different phase of the circuit breaker. The fourth compartment houses the contact operating mechanism while the fifth compartment houses the auxiliary components. A tie bar extends through all of the compartments and connects the operating mechanism to the movable contact arms of all three phases so that operation of all phases will be simultaneous. In addition, a common trip bar for automatic tripping extends across all five compartments.

As will hereinafter be explained in detail, suitable extentions and connections are provided on the tie bar and common trip bar for operation of auxiliary components, and the operation of the circuit breaker by auxiliary trip devices.

Accordingly a primary object of the instant invention is to provide a novel construction for a molded case circuit breaker.

Another object is to provide a circuit breaker of this type in which the auxiliary components are isolated from the current carrying elements of the circuit breaker.

Still another object is to provide a circuit breaker of this type having individual parallel compartments for the current carrying and trip elements of each phase of the circuit breaker, another parallel compartment for the contact operating mechanism, and still another parallel compartment for auxiliary components.

A further object is to provide a circuit breaker of this type which is shorter and more shallow than prior art units of the same voltage and current carrying capacities.

A still further object is to provide a circuit breaker of this type which is of compact construction yet permits the incorporation of many auxiliary components.

These as well as further objects of this invention shall become readily apparent after reading the following description of the accompanying drawings in which:

FIGURE 1 is a plan view of a circuit breaker constructed in accordance with the teachings of the instant invention with the cover removed to reveal details of the internal elements.

FIGURES 2, 3 and 4 are cross sections taken through lines 22, 33 and 44, respectively, of FIGURE 1 looking in the direction of the respective arrows.

Circuit breaker includes molded housing formed of base 11 and removable cover 12 held in place by fasteners 13. Base 11 is provided with parallel sidewalls 14 and 15 as well as internal partitions 16-19 which 3,243,563 Patented Mar. 29, 1966 extend parallel to sidewalls 14, 15 so as to define five parallel compartments within base 11. In a similar manner, cover 12 is provided with sidewalls and partitions which appear as forward extensions of sidewalls 14, 15 and partitions 16-19.

As clearly seen in FIGURE 1, the outer compartments and the center compartment each has the current carrying elements and the automatic trip elements for a single phase of circuit breaker 10. One of the other compartments has as contact operating mechanism 20 and the last compartment has a plurality of auxiliary components which will hereinafter be described indetail. Transversely extending common trip bar and tie bar project through all five compartments for purposes to be hereinafter explained.

Contact operating mechanism 20 may be any one of many trip free mechanisms well known to the art. Reference is made to FIGURE 3, in particular, and the description thereof which follows for a cursory explanation of operating mechanism 20.

Mechanism 20 includes cradle 21 pivotally mounted at pin 22 to mechanism frame 23. Screws 36 received by base inserts 37 fixedly secure mechanism frame 23 to base 11. Toggle links 26, 27 joined at knee pin 28, connect cradle 21 to arm 33 at pins 29 and 32, respectively. Clamp 34 connects arm 33 to tie bar 30 at a point remote from pivot pin 32. One end of operating springs 38 are connected to plate 39 pivotally mounted to toggle knee 28. The other end of springs 38 are connected at the web position of extension 24 for handle 4%, with handle 40 extending through cover aperture 41.

Latch tip 42, at the left of cradle 21, is engaged by intermediate latch member 43 which is pivotally mounted to frame 23 at pin 44. Torsion spring 45 mounted to pin 44 biases intermediate latch member 43 in a clockwise direction with respect to FIGURE 3 and engages extension 46 of common trip bar extension 47 so as to bias common trip bar 25 in a counterclockwise direction with respect to FIGURE 3. Adjusting screw 48 extends through a leg of extension 47 to engage frame cross member 49 and thereby limit the counterclockwise movement and establish the latching position of trip bar 25.

With trip bar 25 in its most counterclockwise position, as illustrated in FIGURE 3, latch tip 47a of extension 47 is positioned so as to block counterclockwise movement of intermediate latch member 43. However, when trip bar 25 is rotated slightly clockwise from the position illustrated in FIGURE 2, latch tip 47a is aligned with aperture 43a of latch member 43 so that latch member 43 is no longer restrained against counterclockwise move? ment. With member 43 pivoted counterclockwise from its position in FIGURE 3, upward movement of latch tip 42 is no longer blocked and under the urging of operating springs 48 upper toggle link pivot 29 will move to the right of the line of action of springs 38 so that toggle knee 28 will move to the left with respect to FIGURE 3. Thus, toggle 26, 27 will collapse moving pin 32 upwardly rotating tie bar 30 in a counterclockwise direction with respect to FIGURE 3.

The current carrying elements of all three phases A, B, C are identical, so that only the elements of phase A will be described. Particular reference is made to FIGURE 2. With the circuit breaker closed the current path through phase A is as follows. Wire grip 51A, terminal strip 52A, stationary contact 53A, movable contact 54A, movable contact arm 55A, flexible braid 56A, L-shaped strap 57A, trip member frame 58A, and terminal 59A.

Clamp 69A fixedly secures member 61A to tie bar 30 with pin 62A pivotally mounting contact arm 55A to member 61A. Extension 61A of member 61A projects into notch 55A to limit the pivotal movement of arm 55A.

Compression spring 63 furnishes the pressure to establish good electrical contact between cooperating contacts 53A and 54A by bearing against arm 55A and member 61AM.

As fully described irTtlTe copendingmpplica'tien Serial No. 174,124, filed February 19, 1962, with M. V. Zubaty as inventor, entitled Automatic Trip Device, now U.S. Patent No. 3,180,953, and assigned to the assignee of the instant invention, automatic trip unit 70A is provided with a delay tripping means in the form of bimetal 71A fixedly secured at its lower end to one of the legs of member 58A. The upper end of bimetal 71A is free to deflect to the right with respect to FIGURE 2 and when sulficiently deflected engages leg 72A of trip bar extension 72A so as to rotate trip bar 25 in a clockwise direction with respect to FIGURE 2 to cause automatic tripping of circuit breaker 10.

Automatic trip unit 70A is also provided with an instantaneous trip means in the form of the magnetic field, accompanying current flow through member 58A, which passes through pivoted armature 73A. When the current through member 58A is of sufiicient magnitude, the upper end of armature 73A moves to the left against the force of leaf spring 74A and engages leg 72A of trip bar extension 72A so as to rotate trip bar 25 in a clockwise direction with respect to FIGURE 2 to cause tripping of circuit breaker 10.

In a manner well known to the art, contact arms 55B and 55C are mounted to tie bar 31 in the same manner previously described for the connection of contact arm 55A. Common trip bar extensions 72B and 72C (FIG- URE 1) are provided so as to be engageable by the movable elements of automatic trip units 70B and 70C, respectively, to bring about automatic tripping of circuit breaker should faults occur in B or C phases.

As clearly seen in FIGURE 1, contact operating mechanism is positioned in the compartment between phases A and B. The compartment formed between phases B and C by partitions 16 and 17 houses shunt trip device 89 and auxiliary switches 82, 83 (FIGURE 4). Each of the auxiliary switches 82, 83 is secured to base 11 by a bracket 84 and a screw 85. With circuit breaker 10 in the open position springs 82a and 83a mounted to frames 84 are positioned immediately to the left of operating members 8212 and 83b of auxiliary switches 82 and 83, respectively.

Screw 86 and clamp 37 fixedly secure member 88 to tie bar 30. Member 88 is provided with leg 83a which extends generally parallel to spring leg 82a. Extension 88b, disposed at the free end of leg 88a, extends to the right with respect to FIGURE 4 so as to be engageable with spring leg 82a when circuit breaker 10 is closed. Connecting rod 89 extends through clearance apertures in spring legs 82a and 83a and is provided with enlarged deformations 89a and 89b which are operatively positioned so that movement of spring leg 82a to the right with respect to FIGURE 4 causes a rightward movement of spring leg 83a.

With circuit breaker 10 open, tip 88b of leg 88a is positioned to the left so that spring leg 82a assumes a position to the left of operating member 82b. Legs 82a and 83a are, under these circumstances, biased to a position clear of switch operating members 82b and 83b. When tie bar is pivoted clockwise to bring back closing of circuit breaker 10, the upper end 88b of leg 88a moves to the right with respect to FIGURE 4 thereby moving the upper ends of spring legs 82a and 83a to the right with respect to FIGURE 4 to engage operating member 82b and 83b thereby operating auxiliary switches 82 and 83, respectively.

In a manner well known to the art, suitable flexible leads (not shown) extend through apertures (not shown) in base 11 for connecting terminals 91 and 92 of auxiliary switches 82 and 83 respectively to external circuits.

Shunt trip device 80 includes generally C-shaped frame 93 secured to base 11 by screw 94. Operating coil 95 wound on bobbin 96 is connected to the external circuit by leads (not shown) which extend through apertures (not shown) in base 11, in a manner well known to the art. Bobbin 96 is mounted to pole piece 97 secured to frame 93 and extends parallel to the arms thereof. Reduced extension 98 projects through aperture 99 near the center of armature 190 to provide a pivotal support for the latter. The portion of armature 1% below extension 98 projects in front of pole piece 97 while the portion extending above extension 98 is engaged by tension spring 101.

Spring 181 extends through a clearance aperture in one leg of generally U-shaped body 102 and is anchored to the other leg thereof. Rivets 1G3 fixedly secure armature 1% to frame 93 and spring 101 biases armature 100 in a counterclockwise direction away from pole piece 97.

0 Adjusting screw 164 extends through the leg of bracket 102 with the clearance aperture for spring 101 so as to limit the counterclockwise movement of armature 100. \Nhen coil is energized, armature 1G!) is attracted to pole piece 97 with the upper end of armature moving to the right with respect to FIGURE 4 into engagement with common trip bar extension 110. This causes a clockwise movement of trip bar 25 thereby tripping circuit breaker 10.

Thus, this invention provides a novel construction for a multiphase circuit breaker in which the contact operating mechanism is disposed in a compartment which is isolated from the current carrying and automatic tripping elements. In addition all auxiliary components are disposed in a separa.e compartment which is completely isolated from the current carrying and automatic trip elements of the circuit breaker. By isolating the contact operating mechanism 2G a more shallow and shorter circuit breaker construction is achieved. By isolating the auxiliary devices from the current carrying components many insulating problems are substantially eliminated and a greater number of auxiliary components may be mounted in the circuit breaker without hazard.

Although there has been described a preferred embodiment of this novel invention, many variations and modi-. fications will now be apparent to those skilled in the art. Therefore, this invention is to be limited, not by the specific disclosure herein, but only by the appending claims.

The embodiments of the invention in which an exclusive privilege or property is claimed are defined as follows.

I claim:

1. A multiphase circuit breaker including a housing having means defining a plurality of elongated side by side compartments; each phase of said circuit breaker having current carrying elements including a pair of cooperating contacts; said current carrying elements of a first phase disposed within a first of said compartments; said current carrying elements of a second phase disposed within a second of said compartments; an operating mechanism in a third of said compartments; a transversely extending tie bar operatively connecting the operating mechanism to the current carrying elements of said first and said second phases whereby'the cooperating contacts thereof are operable into and out of engagement by said operating mechanism; an auxiliary device in a fourth of said compartments, electrically isolated from said first, second and third compartments; an operative connection between said device and said ope-rating mechansm whereby operation of one of said mechanism and said device brings about operation of the other of said mechanism and said device.

2. A multiphase circuit breaker including a housing having means defining a plurality of elongated side by side compartments; each. phase of said circuit breaker having current carrying elements including a pair of cooperating contacts; said current carrying elements of a first phase disposed within a first of said compartments; said current carrying elements of a second phase disposed Within :a second of said compartments; an operating mechanism in a third of said compartments; a trans versely extending tie bar operatively connecting the operating mechanism to the current carrying elements of said first and said second phases whereby the cooperating contacts thereof are operable into and out of engagement by said operating mechanism; an auxiliary device in a fourth of said compartments, electrically isolated from said first, second and third compartments; means engaging a portion of said tie bar extending through said fourth compartment; said last recited means also engaging said device for operation thereof in response to movement of said tie bar.

3. A multiphase circuit breaker including a housing having means defining a plurality of elongated side by side compartments; each phase of said circuit breaker having current carrying elements including a pair of cooperating contacts; said current carrying elements of a first phase disposed within a first of said compartments; said current carrying elements of a second phase disposed within a second of said compartments; an operating mechanism in a third of said compartments; a transversely extending tie bar operatively connecting the operating mechanism to the current carrying elements of said first and said second phases whereby the cooperating contacts thereof are operable into and out of engagement by said operating mechanism; an auxiliary device in a fourth of said compartments, electrically isolated from said first, second and third compartments; each of said phases having an automatic trip unit disposed in the compartment of the respective phase; a transversely extending trip bar for maintaining said operating mechanism in a reset position wherein said mechanism is effective to bring said cooperating contacts into engagement; each of trip units, upon the occurrence of a fault condition moving said bar to a trip position to release said mechanism and automatically bring said cooperating contacts out of engagement; said device engageable with a portion of said trip bar extending through said fourth compartment for operating said trip bar to said trip position.

4. The circuit breaker of claim 3 in which there is another auxiliary device in said fourth compartment; an operative connection between said tie bar and said another auxiliary device for operation of the latter in response to movement of said tie bar.

5. A multiphase circuit breaker including a housing having means defining a plurality of elongated side by side compartments; each phase of said circuit breaker having current carrying elements including a pair of cooperating contacts; said current carrying elements of a first phase disposed within a first of said compartments; said current carrying elements of a second phase disposed within a second of said compartments; said current carrying elements for a third phase disposed within a third of said compartments; an operating mechanism in a fourth of said compartments; a transversely extending tie bar operatively connecting the operating mechanism to the current carrying elements of said first, said second and said third phases whereby the cooperating contacts thereof are operable into and out of engagement by said operating mechanism; an auxiliary device in a fifth of said compartments, electrically isolated from said first, second, third and fourth compartments; an operative connection between said device and said operating mechanism whereby operation of one of said mechanism and said device brings about operation of the other of said mechanism and said device; said fourth compartment positioned between said first and said second compartments; said fifth compartment positioned between said second and said third compartments.

6. A multiphase circuit breaker including a housing having means defining a plurality of elongated side by side compartments; each phase of said circuit breaker having current carrying elements including a pair of cooperating contacts; said current carrying elements of a first phase disposed within a first of said compartments; said current carrying elements of a second phase disposed within a second of said compartments; said current carrying elements for a third phase disposed within a third of said compartments; an operating mechanism in a fourth of said compartments; a transversely extending tie bar operatively connecting the operating mechanism to the current carrying elements of said first, said second and said third phases whereby the cooperating contacts thereof are operable into and out of engagement by said operating mechanism; an auxiliary device in a fifth of said compartments, electrically isolated from said first, second, third and fourth compartments; means engaging a portion of said tie bar extending through said fifth compartment; said last recited means also engaging said device for operation thereof in response to movement of said tie bar.

7. A multiphase circuit breaker including a housing having means defining a plurality of elongated side by side compartments; each phase of said circuit breaker having current carrying elements including a pair of cooperating contacts; said current carrying elements of a first phase disposed within a first of said compartments; said current carrying elements of a second phase disposed within a second of said compartments; said current carrying elements of a third phase disposed within a third of said compartments; an operating mechanism in a fourth of said compartments; a transversely extending tie bar operatively connecting the operating mechanism to the current carrying elements of said first, said second and said third phases whereby the cooperating ocntacts thereof are operable into and out of engagement by said operating mechanism; an auxiliary device in a fifth of said compartments, electrically isolated from said first, second, third and fourth compartments; each of said phases having an automatic trip unit disposed in the compartment of the respective phase; a transversely extending trip bar for maintaining said operating mechanism in a reset position wherein said mechanism is effective to bring said cooperating contacts into engagement; each of trip units, upon the occurrence of a fault condition in its respective phase, operating said bar to a trip position to release said mechanism and automatically bring said cooperating contacts out of engagement; said device engageable with a portion of said trip bar extending through said fifth compartment for operating said trip bar to said trip position.

8. The circuit breaker of claim 7 in which there is another auxiliary device in said fifth compartment; an operative connection between said tie bar and said another auxiliary device for operation of the latter in response to movement of said tie bar.

References Cited by the Examiner UNITED STATES PATENTS 2,154,703 4/1939 Sandin 20088 X KATHLEEN H. CLAFFY, Primary Exam'iner.

H. O, JONES, Assistant Examiner. 

1. A MULTIPHASE CIRCUIT BREAKER INCLUDING A HOUSING HAVING MEANS DEFINING A PLURALITY OF ELONGATED SIDE BY SIDE COMPARTMENTS; EACH PHASE OF SAID CIRCUIT BREAKER HAVING CURRENT CARRYING ELEMENTS INCLUDING A PAIR OF COOPERATING CONTACTS; SAID CURRENT CARRYING ELEMENTS OF A FIRST PHASE DISPOSED WITHIN A FIRST OF SAID COMPARTMENTS; SAID CURRENT CARRYING ELEMENTS OF A SECOND PHASE DISPOSED WITHIN A SECOND OF SAID COMPARTMENTS; AN OPERATING MECHANISM IN A THIRD OF SAID COMPARTMENTS; A TRANSVERSELY EXTENDING TIE BAR OPERATIVELY CONNECTING THE OPERATING MECHANISM TO THE CURRENT CARRYING ELEMENTS OF SAID FIRST AND SAID SECOND PHASES WHEREBY THE COOPERATING CONTACTS THEREOF ARE OPERABLE INTO AND OUT OF ENGAGEMENT BY SAID OPERATING MECHANISM; AN AUXILIARY DEVICE IN A FOURTH OF SAID COMPARTMENTS, ELECTRICALLY ISOLATED FROM SAID FIRST, SECOND AND THIRD COMPARTMENTS; AN OPERATIVE CONNECTION BETWEEN SAID DEVICE AND SAID OPERATING MECHAMSM WHEREBY OPERATION OF ONE OF SAID MECHANISM AND SAID DEVICE BRINGS ABOUT OPERATION OF THE OTHER OF SAID MECHANISM AND SAID DEVICE. 